Does placing an intraosseous (IO) device affect a fistula?

Intraosseous Access Does Not Affect Arteriovenous Fistulas

Placing an intraosseous (IO) device does not directly affect an arteriovenous (AV) fistula, as these are anatomically separate structures—IO access is placed into bone marrow cavities while fistulas are vascular connections between arteries and veins. However, the limb containing a functioning or maturing AV fistula should be avoided for IO placement to preserve the fistula for dialysis access.

Anatomical and Clinical Considerations

Why IO Access Doesn't Directly Affect Fistulas

• IO access targets the bone marrow cavity through sites like the proximal tibia (2 cm distal to tibial tuberosity, 1 cm medial) or the humerus, providing access to the noncollapsible venous plexus within bone 1.
• AV fistulas are superficial vascular structures created surgically between arteries and veins, typically in the forearm or upper arm, and do not involve bone marrow spaces 2.
• These structures occupy completely different anatomical compartments with no direct communication.

Critical Limb Preservation Principle

• Upper limb veins should be preserved in patients with chronic kidney disease who may need future dialysis access, which means avoiding any vascular access (including IO) in limbs designated for fistula creation 2.
• If a patient has an existing functioning fistula, that limb should be avoided for IO placement to prevent any risk of compromising the fistula through compartment syndrome, infection, or other complications that could theoretically extend to surrounding tissues 3.

Recommended IO Placement Sites

Preferred Sites in Order of Priority

• Proximal tibia (2 cm distal to tibial tuberosity, 1 cm medial to tibial plateau) is the first-line site for IO access 1.
• Humerus serves as an alternative preferred site 1.
• Avoid the limb with an AV fistula even though IO access won't directly damage the fistula itself—this preserves the limb for fistula function and avoids potential complications 2.

Emergency Situations

• IO access is a Class I recommendation for rapid first-line vascular access in cardiac arrest and critically ill patients when peripheral IV cannot be quickly established 4, 1.
• In pediatric cardiac arrest, IO access is rapid, safe, effective, and acceptable as initial vascular access 4.
• All IV medications can be administered via IO, including epinephrine, adenosine, fluids, blood products, and catecholamines, with onset of action comparable to venous administration 4.

Important Safety Considerations

Complications to Monitor

• Remove IO devices within 24 hours once alternative IV access is established to minimize risk of osteomyelitis 1.
• Extravasation occurs in approximately 7.4% of IO placements and is the most common complication 5.
• Serious complications are rare but documented, including tibial osteomyelitis requiring multiple debridements, compartment syndrome, and in extreme cases amputation 6, 3.
• Intra-articular misplacement into the knee joint has been reported and could cause septic arthritis if unrecognized 7.

Technical Execution

• Ensure proper skin antisepsis prior to device insertion to reduce infection risk 6.
• Avoid epiphyseal growth plates in pediatric patients 1.
• Follow each medication with a saline flush to promote entry into central circulation 4.
• Use manual pressure or infusion pump for viscous drugs or rapid fluid boluses 4.

Clinical Algorithm for IO Placement in Patients with Fistulas

1. Identify if patient has an AV fistula and which limb it occupies
2. Select contralateral limb or lower extremity for IO placement (preferably proximal tibia)
3. If bilateral upper extremity fistulas exist, use lower extremity IO sites exclusively
4. In neonates or delivery room settings, umbilical venous catheterization is preferred over IO 4
5. Remove IO device as soon as peripheral or central IV access is secured, ideally within 24 hours 1